右心室不同部位起搏对左心室收缩功能的影响

目的:比较右心室心尖(RVA)及流出道间隔部(RVOT-S)起搏对左心室收缩功能的影响,探讨合理的右心室起搏部位。方法:自2007年8月~2009年12月,36例左室收缩功能正常的完全性房室传导阻滞患者,随机纳入RVA和RVOT-S起搏组,起搏器植入12月后分别测定左室射血分数(LVEF),左室收缩末容量(LVESV),主动脉瓣口速度时间积分(VTI),主动脉与肺动脉瓣开放时间差(QAO-QP),房颤负荷(AFb),自动模式转换(AMS),血浆脑钠尿肽原(NT-proBNP)变化,QRS波宽度,比较两组的差别。结果:起搏12月后RVOT-S组LVEF及VTI明显高于RVA组(均P<0.05);LVESV,QAO-QP,NT-BNP,AFb,AMS及QRS波宽度明显低于RVA组(均P<0.05)。结论:与RVOT-S组相比,RVA长期起搏可导致明显左右心室间以及左室内收缩不同步及左室重构,减低左心室收缩功能,对心室依赖起搏患者应首选RVOT-S为心室电极植入部位。

Impact on left ventricular systolic function by long-term permanent right ventricular pacing in different sites

AIM:To compare the effects on left ventricular systolic function by long-term permanent pacing in right ventricular apex(RVA) and right ventricular outflow tract septal(RVOT-S) and to investigate the optimal right ventricular site for permanent pacing.METHODS:Thirty-six patients diagnosed as having complete atrial-ventricular block(CAVB) and normal left ventricular systolic function and who were hospitalized during the period of August 2007 to December 2009 male/female=20/16,mean age:(51.3±22.2) years] were randomly assigned to RVA pacing group and RVOT-S pacing group.Twelve months after implantation of permanent pacemakers,left ventricular ejection fraction(LVEF),left ventricular end-systolic volume(LVESV),aortic velocity time integral(VTI),activation delay between aortic and pulmonary artery valve(QAO-QP),atrial fibrillation burden(AFb),automatic mode switch(AMS),serum NT-Pro-BNP(NT-proBNP) and width of QRS were analyzed and compared between groups.RESULTS:After 12 months pacing,LVEF and VTI in RVOT-S group were significant higher than those in RVA group(P<0.05).LVESV,QAO-QP,AFb,AMS,N-BNP and QRS width in RVOT-S group were statistically lower than those in RVA group(P<0.05).CONCLUSION:Long-term RVA pacing could induce inter-and intraventricular desynchrony and left ventricular remodeling,which would impair the left ventricular systolic function.RVOT-S could be the optimal site for permanent ventricular pacing.